RESUMO
In vertebrate animals, pleural and peritoneal cavities are repositories of milky spots (MS), which constitute an organised coelom-associated lymphomyeloid tissue that is intensively activated by Schistosoma mansoni infection. This study compared the reactive patterns of peritoneal MS to pleural MS and concluded from histological analysis that they represent independent responsive compartments. Whole omentum, lungs and the entire mediastinum of 54 S. mansoni-infected mice were studied morphologically. The omental MS of infected animals were highly activated, modulating from myeloid-lymphocytic (60 days of infection) to lymphomyeloid (90 days of infection) and lymphocytic or lymphoplasmacytic (160 days of infection) types. The non-lymphoid component predominated in the acute phase of infection and was expressed by monocytopoietic, eosinopoietic and neutropoietic foci, with isolated megakaryocytes and small foci of late normoblasts and mast cells. Nevertheless, pleural or thoracic MS of infected mice were monotonous, consisting of small and medium lymphocytes with few mast and plasma cells and no myeloid component. Our data indicate that compartmentalisation of the MS response is dependent on the lymphatic vascularisation of each coelomic cavity, limiting the effects or consequences of any stimulating or aggressive agents, as is the case with S. mansoni infection.
Assuntos
Tecido Linfoide/patologia , Omento/patologia , Pleura/patologia , Esquistossomose mansoni/patologia , Animais , Tecido Linfoide/parasitologia , Masculino , Camundongos , Microscopia Confocal , Omento/parasitologia , Pleura/parasitologiaRESUMO
STUDY OBJECTIVE: To present the clinical, radiologic, and pathologic aspects of 24 cases of human pulmonary dirofilariasis (HPD) from São Paulo, Brazil. DESIGN: Retrospective study of 24 patients with a confirmed diagnosis of HPD over a 14-year period (from February 1982 to June 1996). SETTING: Thoracic Surgery and Pulmonary Division, University of São Paulo and Hospital Albert Einstein, São Paulo, Brazil. RESULTS: Seventeen patients were male (70.1%) and seven were female (29.9%). Their mean age was 51.4 years. Fifty-four percent of the patients were asymptomatic and 75% had a well-circumscribed noncalcified peripheral subpleural pulmonary nodule on the chest radiograph and thoracic CT scan, located preferentially in the lower lobes. The diagnosis was made after thoracotomy and wedge resections in 16 patients, by videothoracoscopy in six, after a pleural biopsy in one, and after necropsy in one. The pathologic examination of all the nodules revealed a central zone of necrosis, surrounded by a narrow granulomatous zone and peripherally by fibrous tissue. Pulmonary vessels exhibit varying degrees of endarteritis. In all cases, a dead worm, usually necrotic and fragmented, was found. CONCLUSIONS: A subpleural, noncalcified pulmonary nodule in the appropriate clinical and epidemiologic setting should alert the clinician, radiologist, or pathologist to the possibility of Dirofilaria. HPD should be considered in the differential diagnosis of pulmonary nodules.
Assuntos
Dirofilariose/epidemiologia , Pneumopatias Parasitárias/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Arterite/parasitologia , Arterite/patologia , Biópsia , Brasil/epidemiologia , Diagnóstico Diferencial , Dirofilariose/diagnóstico , Dirofilariose/diagnóstico por imagem , Dirofilariose/patologia , Feminino , Fibrose , Granuloma/parasitologia , Granuloma/patologia , Humanos , Pulmão/irrigação sanguínea , Pneumopatias Parasitárias/diagnóstico , Pneumopatias Parasitárias/diagnóstico por imagem , Pneumopatias Parasitárias/patologia , Masculino , Pessoa de Meia-Idade , Necrose , Pleura/parasitologia , Pneumonectomia , Estudos Retrospectivos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Nódulo Pulmonar Solitário/epidemiologia , Nódulo Pulmonar Solitário/parasitologia , Toracoscopia , Toracotomia , Tomografia Computadorizada por Raios X , Gravação em VídeoRESUMO
Large tumors removed from the lower abdomen and pleural cavity of a 24-year-old male Amerindian in Paraguay consisted mainly of multitudes of minute, proliferating, acephalic cestode larvae embedded in fibrous tissue. The parasite resembled Sparganum proliferum Stiles 1908 but was markedly less differentiated. From a review of the literature and examination of available reference material, it is concluded that in addition to the present one there are eight well documented cases of proliferating acephalic larval cestode infection in man: five in Japan and one in Florida (USA) that were S. proliferum, one in Pennsylvania (USA) that was an undifferentiated cysticercus or cysticercoid, and one in Taiwan that probably was an undifferentiated tetrathyridium. In four other cases the parasites are reclassified as being of doubtful nature in three and a racemose cysticercus in one. Review of the known species of proliferating cestode larvae naturally occurring in animals failed to identify possible sources of the acephalic forms observed in man.